A Hero Ain't Nothin' But a Sandwich (1978) - Trailer

Benjie is a troubled teen in Los Angeles, living with his grandmother, mother, and her new boyfriend. Traumatized by his father's desertion and the situation at home, Benjie gets introduced to heroin. The downward spiral begins. At school he faces conflict between the two teachers he respects: Nigeria who emphasizes African history and is hostile to white teachers like Mr. Cohen, who pursues racial harmony. Benjie's family must come to terms with the devastation he has created in his life and make changes which affect them all.

Director: Ralph Nelson
Writers: Alice Childress (novel), Alice Childress (screenplay)
Stars: Cicely Tyson, Paul Winfield, Larry B. Scott

https://www.imdb.com/title/tt0077669/